# Psi to Megapascals (psi to MPa)

> Convert psi to megapascals: 1 psi = 0.00689476 MPa. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

- Page id: `psi-to-mpa` · Quantity: Pressure (`pressure`, base unit Pa) · Tool: `convert_units`
- Canonical page: https://tttkmbb.com/conversion/psi-to-mpa · This document: https://tttkmbb.com/conversion/psi-to-mpa.md · JSON: https://tttkmbb.com/conversion/psi-to-mpa.json (add `?value=` for a result)

## Formula

- `1 psi = 0.00689476 MPa`
- `megapascals = psi × 0.006894757293`
- Reverse: `psi = megapascals × 145.0377377`

The factor follows from the SI definitions of both units (NIST SP 811); values below are rounded to 6 significant figures, the API returns up to 12.

## Worked examples

- 5 psi = 0.0344738 MPa
- 12.5 psi = 0.0861845 MPa
- 100 psi = 0.689476 MPa

## Conversion table

| Psi (psi) | Megapascals (MPa) |
| --- | --- |
| 1 | 0.00689476 |
| 2 | 0.0137895 |
| 3 | 0.0206843 |
| 4 | 0.027579 |
| 5 | 0.0344738 |
| 6 | 0.0413685 |
| 7 | 0.0482633 |
| 8 | 0.0551581 |
| 9 | 0.0620528 |
| 10 | 0.0689476 |
| 15 | 0.103421 |
| 20 | 0.137895 |
| 25 | 0.172369 |
| 30 | 0.206843 |
| 40 | 0.27579 |
| 50 | 0.344738 |
| 75 | 0.517107 |
| 100 | 0.689476 |
| 200 | 1.37895 |
| 250 | 1.72369 |
| 500 | 3.44738 |
| 1000 | 6.89476 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=psi&to_unit=MPa` → unified JSON envelope with `result.values.result`, `formula`, `factor`, `sources`, `freshness`
- MCP: server `https://tttkmbb.com/mcp`, tool `convert_units` with `{"value":5,"from_unit":"psi","to_unit":"MPa"}`
- All pressure units: https://tttkmbb.com/api/v1/units?quantity=pressure · full converter: [Pressure Converter](https://tttkmbb.com/conversion/pressure.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**How many megapascals are in one psi?**

1 psi = 0.00689476 MPa. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

**What is the formula to convert psi to megapascals?**

Multiply the value in psi by 0.006894757293: megapascals = psi × 0.006894757293. For example, 5 psi = 0.0344738 MPa.

**How do I convert megapascals back to psi?**

Multiply by the inverse factor 145.0377377 (psi = megapascals × 145.0377377), or use the megapascals-to-psi page.

## Related conversions

- [Megapascals to psi](https://tttkmbb.com/conversion/mpa-to-psi.md) (reverse)
- [Psi to Bar](https://tttkmbb.com/conversion/psi-to-bar.md)
- [Bar to Psi](https://tttkmbb.com/conversion/bar-to-psi.md)
- [Psi to Kilopascals](https://tttkmbb.com/conversion/psi-to-kpa.md)
- [Kilopascals to Psi](https://tttkmbb.com/conversion/kpa-to-psi.md)
- [Bar to Kilopascals](https://tttkmbb.com/conversion/bar-to-kpa.md)
- [Kilopascals to Bar](https://tttkmbb.com/conversion/kpa-to-bar.md)
- [Atmospheres to Pascals](https://tttkmbb.com/conversion/atm-to-pa.md)
- [Pascals to Atmospheres](https://tttkmbb.com/conversion/pa-to-atm.md)

## Data Sources

- NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors — https://www.nist.gov/pml/special-publication-811 (standard, retrieved 2026-09-24)
- BIPM – The International System of Units (SI Brochure, 9th edition) — https://www.bipm.org/en/publications/si-brochure (standard, retrieved 2026-09-24)
- Wikipedia – Conversion of units — https://en.wikipedia.org/wiki/Conversion_of_units (reference, retrieved 2026-09-24)